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CHAR (Transact-SQL)

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Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric

Returns the single-byte character with the specified integer code, as defined by the character set and encoding of the default collation of the current database.

Transact-SQL syntax conventions

Syntax

CHAR ( integer_expression )

Arguments

integer_expression

An integer from 0 through 255. CHAR returns a NULL value for integer expressions outside this input range or not representing a complete character.

CHAR also returns a NULL value when the character exceeds the length of the return type.

Many common character sets share ASCII as a subset and returns the same character for integer values in the range 0 through 127.

Note

Some character sets, such as Unicode and Shift Japanese Industrial Standards, include characters that can be represented in a single-byte coding scheme, but require multibyte encoding. For more information on character sets, see Single-Byte and Multibyte Character Sets.

Return types

char(1)

Remarks

Use CHAR to insert control characters into character strings. This table shows some frequently used control characters.

Control character Value
Tab char(9)
Space char(32)
Line feed char(10)
Carriage return char(13)

Examples

A. Use ASCII and CHAR to print ASCII values from a string

This example prints the ASCII value and character for each character in the string New Moon.

SET TEXTSIZE 0;
-- Create variables for the character string and for the current
-- position in the string.
DECLARE @position INT, @string CHAR(8);
-- Initialize the current position and the string variables.
SET @position = 1;
SET @string = 'New Moon';
WHILE @position <= DATALENGTH(@string)
   BEGIN
   SELECT ASCII(SUBSTRING(@string, @position, 1)),
      CHAR(ASCII(SUBSTRING(@string, @position, 1)))
   SET @position = @position + 1
   END;
GO

Here's the result set.

----------- -
78          N
----------- -
101         e
----------- -
119         w
----------- -
32
----------- -
77          M
----------- -
111         o
----------- -
111         o
----------- -
110         n

B. Use CHAR to insert a control character

This example uses CHAR(13) to print the name and e-mail address of an employee on separate lines, when the query returns its results as text. This example uses the AdventureWorks2022 database.

SELECT p.FirstName + ' ' + p.LastName + CHAR(13) + pe.EmailAddress
FROM Person.Person p
INNER JOIN Person.EmailAddress pe
    ON p.BusinessEntityID = pe.BusinessEntityID
        AND p.BusinessEntityID = 1;
GO

Here's the result set.

Ken Sanchez
[email protected]

C. Use ASCII and CHAR to print ASCII values from a string

This example assumes an ASCII character set. It returns the character value for six different ASCII character number values.

SELECT CHAR(65) AS [65], CHAR(66) AS [66],
CHAR(97) AS [97], CHAR(98) AS [98],
CHAR(49) AS [49], CHAR(50) AS [50];

Here's the result set.

65   66   97   98   49   50
---- ---- ---- ---- ---- ----
A    B    a    b    1    2

D. Use CHAR to insert a control character

This example uses CHAR(13) to return information from sys.databases on separate lines, when the query returns its results as text.

SELECT name, 'was created on ',
    create_date,
    CHAR(13),
    name,
    'is currently ',
    state_desc
FROM sys.databases;
GO

Here's the result set.

name                                      create_date               name                                  state_desc
--------------------------------------------------------------------------------------------------------------------
master                    was created on  2003-04-08 09:13:36.390   master                  is currently  ONLINE
tempdb                    was created on  2014-01-10 17:24:24.023   tempdb                  is currently  ONLINE
AdventureWorksPDW2012     was created on  2014-05-07 09:05:07.083   AdventureWorksPDW2012   is currently  ONLINE

E. Use CHAR to return single-byte characters

This example uses the integer and hex values in the valid range for ASCII. The CHAR function is able to output the single-byte Japanese character.

SELECT CHAR(188) AS single_byte_representing_complete_character,
  CHAR(0xBC) AS single_byte_representing_complete_character;
GO

Here's the result set.

single_byte_representing_complete_character single_byte_representing_complete_character
------------------------------------------- -------------------------------------------
ｼ                                           ｼ

F. Use CHAR to return multibyte characters

This example uses integer and hex values in the valid range for Extended ASCII. However, the CHAR function returns NULL because the parameter represents only the first byte of a multibyte character. A char(2) double-byte character can't be partially represented nor divided without some conversion operation. The individual bytes of a double-byte character don't generally represent valid char(1) values.

SELECT CHAR(129) AS first_byte_of_double_byte_character,
  CHAR(0x81) AS first_byte_of_double_byte_character;
GO

Here's the result set.

first_byte_of_double_byte_character first_byte_of_double_byte_character
----------------------------------- -----------------------------------
NULL                                NULL

G. Use CONVERT instead of CHAR to return multibyte characters

This example accepts the binary value as an encoded multibyte character consistent with the default codepage of the current database, subject to validation. Character conversion is more broadly supported and might be an alternative to working with encoding at a lower level.

CREATE DATABASE [multibyte-char-context] COLLATE Japanese_CI_AI;
GO

USE [multibyte-char-context];
GO

SELECT NCHAR(0x266A) AS [eighth-note],
    CONVERT(CHAR(2), 0x81F4) AS [context-dependent-convert],
    CAST(0x81F4 AS CHAR(2)) AS [context-dependent-cast];

Here's the result set.

eighth-note context-dependent-convert context-dependent-cast
----------- ------------------------- ----------------------
♪           ♪                         ♪

H. Use NCHAR instead of CHAR to look up UTF-8 characters

This example highlights the distinction the Unicode standard makes between a character's code point and the code unit sequence under a given encoding form. The binary code assigned to a character in a classic character set is its only numeric identifier.

In contrast, the UTF-8 byte sequence associated with a character is an algorithmic encoding of its assigned numeric identifier: the code point. UTF-8 char and UTF-16 nchar are different encoding forms using 8-bit and 16-bit code units, of the same character set: the Unicode Character Database.

;WITH uni (c)
AS (
    -- BMP character
    SELECT NCHAR(9835)    
    UNION ALL
    -- non-BMP supplementary character or, under downlevel collation, NULL
    SELECT NCHAR(127925)
),
enc (u16c, u8c)
AS (SELECT c, CONVERT(VARCHAR(4), c COLLATE Latin1_General_100_CI_AI_SC_UTF8) FROM uni)
SELECT u16c AS [Music note],
    u8c AS [Music note (UTF-8)],
    UNICODE(u16c) AS [Code Point],
    CONVERT(VARBINARY(4), u16c) AS [UTF-16LE bytes],
    CONVERT(VARBINARY(4), u8c) AS [UTF-8 bytes]
FROM enc;

Here's the result set. These results are generated under a _SC collation with supplementary character support.

Music note Music note (UTF-8) Code Point UTF-16LE bytes UTF-8 bytes
♫ ♫ 9835 0x6B26 0xE299AB
🎵 🎵 127925 0x3CD8B5DF 0xF09F8EB5

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